Digital triac circuit diagram
Posted on Mar 28, 2007 12155
A simple digital circuit is shown can be used to precisely control the AC power supply, the circuit is no digital to analog conversion circuit. In the application, the effectiv
e control of a computer system to send data to the SN74HCT534, after latching, by binary comparator output SN74LS682 with asynchronous counter SN74HC4040 waveform is compared. SN74HC4040 driven by a 1MHz clock, it can provide an accurate 50Hz ~ 60Hz clock. AC power zero crossing, bidirectional optocoupler TIL194B clear the output SN74HC4040 make SN74HC4040 AC signal synchronization. In the zero-crossing point, the binary output of the comparator is invalid. Binary output of the comparator control isolation optocoupler triac TIL3020. After the zero crossing point, the counter starts counting. Binary output of the comparator remains inactive until the counter exceeds SN74HCT534 latched data. SCR optocoupler conducting half cycle of the AC signal until the next zero crossing point was closed soon. Note: You can latch, comparator and control circuit such as optocoupler more communication channels. Clock waveform counter one can drive multiple channels. Between the counter and the binary comparator waveform insert an EPROM or PAL devices, will be able to produce exponential, logarithmic or arbitrary waveform.